84G Popular Editions of Station Bulletins of the 



necessary for selection from natural crossing. The technic of 

 artificial crossing is simple, involving merely the selection and 

 bagging of unopened flowers on the male and female parents, re- 

 moval of stamens from the female flower before pollen has matured 

 and the introduction of pollen from the protected male flower when 

 the stigma of the female flower is receptive. Shortly after the 

 fruits have set the paper bags are removed and sacks of mosquito 

 netting substituted. 



When we know more of the inheritance of apple characters in 

 general it should be a comparatively easy matter to select parents 

 that carry the ones we desire and to unite them in combinations 

 superior or at least different from any we now have. We can not 

 in this way, however, expect to secure new characters. Such devi- 

 ations, if they ever arise, must come from sports, or from crosses 

 outside the range of cultivated varieties. 



As indicated before, it is not safe to make 



How qualities generalizations from the progeny of a first 

 inherit. cross, as first generation crosses inherit the 



characteristics of both parents unseparated, 

 it being only in the second and subsequent generations that the 

 Mendelian pairs segregate (that is, separate in pure, inheritable 

 form in part of the seedlings) ; but the chances are great that in 

 any crossing of apple varieties to-day we are really combining 

 crosses, so that some pairs of characters are split up in what is 

 really the second generation so far as these characters are con- 

 cerned. That is, if we cross two red varieties, and secure some 

 yellow seedlings, it is very good evidence that one or more of the 

 unknown ancestors of the parent varieties must have been yellow- 

 fruited and that the yellow seedlings are pure for that character. 



Even if this be not true it still seems worth while to indicate 

 what seem to be the heritable characters of the parents in these 

 experiments ; for any variety obtained in this way is continued by 

 grafts or buds (parts of the original plant) and so remains con- 



